1. Field of the Invention
The present invention relates to ultrasonic probes used for diagnostic applications, and more particularly, for human body imaging.
2. Related Art
Diagnosing human organs using ultrasound is a well known procedure. Ultrasonic probes are used which employ ultrasonic transducers, with ultrasonic waves being directed from the transducer surface so as to travel through biologic structures under examination. Reflections are obtained each time the ultrasonic waves encounter impedance variation interfaces. As a result, returned echoes are received and processed by the imaging system. Summing all scanning lines received from the transducer provides an image, and the number of scanning lines and the depth of examination govern the scanning rate. Generally speaking, standard ultrasonic probes use a one dimensional (1D) transducer wherein the transducer elements are linearly arranged and no scanning control is implemented in the elevation direction. However, in some probe configurations, multi-dimensional probes (1.5D or 2D) are provided, and the transducer elements are thus arranged in a matrix so as to provide 3D steering capabilities.
Conventionally, ultrasonic probes are connected to a mainframe which is responsible for the processing of electrical signals produced by the probe transducer. The system performs an image capture or rendering operation using data from the region being scanned, and the images so obtained are produced by the synthesizing of information based on a number of different parameters, e.g., the transducer geometry, the number of scanning lines, the depth of examination and the transducer frequency. In common practice, the mainframes are provided with large advanced image settings to produce a diagnosing scan in conformance with the organ structure being examined. Typically, by using a trackball or sensitive pad of an associated keyboard, the imaging system enables a user to access most of the controls for scanning characteristics such as the frame rate, number of focal points, depth, and angle aperture, as well as other settings regarding the mode of scanning, including, e.g., CFM (color flow mapping), B-Mode, C-Mode, CW (continuous wave) and PW (pulsed wave) Doppler and the like, whereas other controls such as master gain, TGC (Time Gain Control), dynamic range, freeze, and measuring tools (for distance, surface, volume and the like) are often provided through activation of direct control buttons or by using cursors for rapid access. Given the complexity of image controls and the close attention that is required in making medical a diagnosis, ultrasound scanning of this kind can, in practice, be a very difficult task.
Considering further prior art of interest, U.S. Pat. No. 5,295,485 to Shinimura and U.S. Pat. No. 5,722,412 to Pflugrath both disclose a handheld device which includes, in the same casing, a transducer array, ASICs (Application Specific Integrated Circuit) or conventional signal processing circuits and a display monitor. The device is battery powered and thus can be used at any desired location. However, integration of all of the various components necessary to the image processing operation results in an apparatus which is heavy and has a reduced lifetime. Further, advanced image processing functionalities like those available in conventional mainframe-based systems cannot always be implemented so that only preliminary diagnostic procedures can be carried out with such prior art devices in attempting to determine the appropriate medical intervention needed by the patient. Accordingly, these devices are essentially dedicated to emergency use where portability and autonomy is required.
In U.S. Pat. No. 6,135,958 to Mikula-Curtis, an ultrasonic scanner is equipped with a remote user interface, including a touch-pad pointing device, so the interface can be placed closer to the user and further away from the ultrasound machine. Such equipment raises the level of comfort in operation the equipment but the use of both hands is still mandatory.
In accordance with the invention, in order to overcome the drawbacks of prior art devices discussed above, there is provided an ultrasonic probe that includes a pointing device mounted on the probe casing or housing so as to enable a user to remotely control the basic functions of the associated imaging system. This pointing device is, in essence, an extension of the original setting controls provided by the system keyboard, so that a user can, at his or her option, either access the major image settings from the remote pointing device or access all of the functions of the system using the system keyboard, the two system interfaces being operable in parallel.
The probe and associated imaging system of the present invention reflect a new approach to operating ultrasonic apparatus. Unlike the conventional systems described above wherein the scanning probe and control interface are separate units and a user must manipulate the ultrasonic instrument with both hands (one for moving and steering the acoustic wave and the other for controlling the image features) and unlike a handheld scanner wherein severe compromises must be made to provide a compact volume at the detriment of image quality, the present apparatus provides a user with an imaging system which comprises at least one ultrasonic probe equipped with a limited remote user interface so that the usual functions of the imaging system can be controlled from probe, thereby significantly improving the comfort level of one using the probe during an examination.
In one embodiment of the invention, the user interface comprises a pointing device located on the probe casing, and the pointing device is a commercially available device as that used in a Notebook computer or in Gamepads or the like. Advantageously, the pointing device is located on a main face of the casing or the housing where there is more room to operate the device and easy access may be had to the device. In connecting the pointing device to the imaging system, a number of suitable techniques can be used including such as single connecting wires or an IR (infrared) line. Of course, there are a wide variety of commercially available pointing devices, and the present invention can employ most, if not all of these, including, in accordance with preferred embodiments of the invention: a sensitive pad controlled by directional actions, a rocking key pointer device, scrolling devices, a track-ball or the like. Among the important manufacturers of these devices are Fujitsu, Techtronics, and InSolutions Corp.
An important advantage of the present invention is the improvement provided thereby in working condition of the sonographers as well as in patient comfort, afforded by putting control of the basic settings of the system at the ready disposition of the user of the probe so as to permit him or her to deal better with the patient. Additional features of the invention include the provision of a one-touch image storage and of a control capability for other optional equipment (e.g., a therapy system or drug delivery functions).
Further features and advantages of the present invention will be set forth in, or apparent from, the detailed description of preferred embodiments thereof which follows.